Method for ultrasonic surgical cleaning of human body members



Jan. 31, 1961 c H. PRANGE 2,970,073

moo FOR uumsourc SURGICAL CLEANING or HUMAN BODY mans Filed Oct. 28. 1959 INVENTOR. CHARLES H. PRANGE ATTORNEYS United States Patent "ice I METHOD FOR ULTRASONIC SURGICAL CLEAN- ING OF HUMAN BODY MEMBERS Filed Oct. 2a, 1959, s. No. 849,416 1 Claims. ci. 134-1) This invention relates to rendering portions of the human body surgically clean, that is, substantially completely free from dirt, grime and germs. More particularly, the invention provides a method of surgically cleaning a portion of the body by immersing it in a germicidal solution while the solution is subjected to ultrasonic vibrations. This application is a continuationin-part of my copending application Serial No. 698,772, filed November 25, 1957, now abandoned.

One advantageous use of the new method is in cleaning a surgeon's hands preparatory to surgery. In order to minimize the danger of infecting a patient while performing a surgical operation, a surgeon normally takes elaborate precautions to prevent the transfer of germs or other source of pathogenic disturbance to the patient from himself, particularly from his hands. He will spend usually anywhere from to 30 minutes in scrubbing his hands and fingernails with a germicidal soap solution to remove all foreign particles and as much of the bacteria as possible. Though such scrubbing is performed vigorously with a stiff brush, the hands are not satisfactorily sterilized by this process alone, and completely sterilized rubber gloves are therefore donned before the operation begins.

Certain disadvantages of this customary cleaning procedure are obvious, and have been recognized for quite some time, but no satisfactory alternative method has been advanced heretofore. The time consumed is quite great, particularly since the surgeon must repeat the prolonged scrubbing proeess before each operation of the day, and he may perform several daily. The time spent cannot be greatly reduced by employing stronger germicidal solutions, because there is a limit to the strength of the solutions to which the surgeon's bands can be safely exposed. As it is, his hands often become quite irritated by the prolonged and vigorous scrubbing with soap and a stiff brush.

The present invention provides a new method for cleaning a surgeon's hands, or in general for rendering a portion of the human body surgically clean for any desired purpose, which requires much less time than customary scrubbing procedures without increasing the strength of the bactericidal solution used. The new method so effectively cleans and sterilizes the hands that a surgeon using it may in many cases operate safely without having to wear rubber gloves. Moreover, the invention substantially eliminates the necessity of subjecting the hands to any irritating brush-scrubbing operation. These advantages are achieved in accordance with the invention by the application of ultrasonic vibrations to the field of surgical cleaning. (As indicated above, the terms surgical cleaning" and surgically clean" are used herein to denote a degree of cleanliness such that the cleaned portion of the body is substantially free of both dirt (grime) and germs, and not in the narrow sense of cleanliness for surgical purposes.)

The method of the invention comprises providing a aqueous solution.

2,970,073 Patented Jan. 31, 1961 solution of a germicide and a surfactant cleansing agent, immersing the portion of the body (generally a portion of the scalp or the limbs but if desired the torso or portions of it) to be cleaned in such solution, and vibrating the solution while such portion of the body is so immersed at a frequency in the range from 10 to 200'kilocycles. It has been found that virtually all foreign material dislodged from the skin, and even from beneath the fingernails, by this method in a period of time generally not exceeding five minutes and often much less. Virtually all germs initially present on the immersed portion of the body are destroyed by the combined effect of the germicidal agent and the ultrasonic vibration ofthe solution. The hands (or other portion of the body) need only be placed at rest in the vibrating solution, and after a few minutes they can be withdrawn surgically clean, and usually sufiiciently free of dirt and germs to permit performing a surgical operation without the need for rubber gloves (though the surgeon may choose to wear gloves as an added precaution, or to protect himself from infection by the patient). Tests have indicated that the success of this new method is due not to any germicidal characteristics of the ultrasonic vibrations, but to the fact tha such vibrations impart to a bacterial surfactant solution an ability to dislodge dirt and foreign particles from the hands or other portions of the body and to destroy bacteria not dislodged therefrom, which cannot be effectively dislodged or destroyed by the same solution when it is not subjected to ultrasonic vibration.

A description and example of a preferred embodiment of the method is given below with reference to the accompanying drawing which schematically illustrates suitable apparatus for carrying out the method. The drawing shows a solution 10 in a container 11, and an ultrasonic generator 12 from which a transducer element 13 extends into the solution. Electrical power for the generator 12 is supplied from a power line 14. The container should be of such size and shape as to permit convenient immersion of a surgeon's hands and arms 15, or whatever other portion of the body is to be cleaned, in the solution 10.

Advantageously the solution 10 may be an aqueous solution containing 0.01% to 10% by weight of a commercial bactericide or germicide and 1% to 5% by weight of a surfactant cleansing agent. In most cases the amount of germicide or bactericide used will be in the range from 0.1% to 5%, and the amount of surfactant, will be in the range from 1% to 5%. In any event the concentration of germicide and surfactant will be those normally employed to make a germicidal cleansing solution in which the hands or other part of the body to be cleaned may be safely immersed.

The germicide may be of any desired bactericidal, fungicidal or germicidal compound or composition which is not injurious to the skin. An advantageous germicide is providone iodine (a reaction product of polyvinyl pyrolidone and iodine in the proportions 10 to 1 by weight), which is customarily employed for germicidal purposes in the form of a l: 1000 aqueous solution. other suitable germicide is zepherin chloride in 1:1000

Others are hexachlorophene (2,2'- methylenebis (3,4,6-trichlorophenol)), phenol itself and certain other phenol derivatives, and cresol and certain cresol derivatives. A sudsing antiseptic detergent cream sold under the trade name Phisohex" by Winthrop Laboratories of New York City, New York, which contains emollients and detergents together with about 3% by weight of hexachlorophene as its principal bactericidal ingredient has been used successfully as the germicide in solutions prepared for use in accordance with the invention. So also has Betadiene, an antiseptic solution 3 of providone iodine sold by Tailby Nason Co., Inc., of Dover, Delaware, and used for purposes of this invention in a 1:1000 aqueous solution.

The surfactant cleansing agent may be any ionic or non-ionic wetting agent, such for example as aryl-alkyl polyester sulfonates and alcohols, hexitol anhydride fatty acid esters, soritan monopalmitate, monolaurate, monostearate, and monoleate, polyoxyethylene derivatives of these sorbitan compounds, alkylnaphthalene sulfonates, hand or toilet soaps, and in general any detergent which is not injurious to the hands or other parts of the body. ux" toilet soap and Ivory" toilet soap, highly refined mild toilet soaps manufactured by Lever Brothers Con.- pany of New York City, New York, and by Proctor and Gamble Company of Cincinnati, Ohio, respectively, are satisfactory surfactants to employ.

The germicidal solution may if desired contain any desired modifying agent, such as glycerine or other bygroscopic material to minimize any drying effect of the solution, emolients sudsing or anti-sudsing agents, etc.

Of course, the invention is not limited to aqueous bactericidal surfactant solutions. Non-aqueous solutions, such as alcoholic solutions, may also be employed. Furthermore, liquids which have bactericidal, germicidal or surfactant properties may in appropriate cases be used without dissolving therein any bactericidal, germicidal, or surfactant agent (as the case may be). The term solution as used herein to define the medium subjected to ultrasonic vibration includes such liquids.

If desired two different solutions may be used serially. For example, the portion of the body to be cleaned may first be immersed in a germicidal solution, after which it may be immersed in another solution or liquid such as alcohol to secure rapid drying, or an emollient solution to soothe the skin. When two separate solutions are used, both, or only one, may be subjected to ultrasonic vibration. The solution may be used cold or warm, but preferably is not heated above 130 F. to avoid burning. The pH of the solution should fall in the range from 5 to 9 to avoid undesirable acid or alkaline effect on the immersed portion of the body.

Any of the commercially available ultrasonic generators, either of the magnetostrictive or crystal type, may be used successfully, provided its output is at a frequency above 10 kilocycles and preferably in the range from 10 to 200 kilocycles. Frequencies of 10 kilocycles and somewhat higher are in the sonic range for many individuals. Although such frequencies are not "ultrasonic to such individuals, their use is within the scope of the invention. They may, however, create objection- 'erator should not generally exceed five watts frequencies. Very satisfactory results are obtained using a generator having an output in the narrower frequency Z range from to 50 kilocycles per second. It should of course have a power output adequate to impart ultrasonic vibrations of effectively high amplitude throughout the volume of solution, and in the size and shape of containers employed. Generally an ultrasonic generator whose output is in the range from 10 to 300 watts is.

adequate and satisfactory. The power output of the genr square ceptirngter of solution surface area, in order to avoid excessively intense vibration of the solution. One very satisfactory apparatus is an electronic ultrasonic generator manufactured and sold by the Pioneer Central Division of Bendix Aviation Corporation of Davenport, Iowa. under the trade designation UG3B." It operates at 117 volts A.C., 60 cycles, with an output frequency of 16 to 18 kilocycles and a maximum power output of 200 watts. The transducer is of the magnetostrictive type. It yields very satisfactory results in combination with a container 11 holding approximately one quart of the aqueous bactericidal solution 10.

Very satisfactory surgical cleaning usually results from immersion of the hands or other parts of the body in the vibrated solution for a period of time in the range from A to 3 minutes. Often an immersion period of about one minute gives good results. In some cases, however, the period of immersion may be less than $6 minute, or longer than 3 minutes.

Using an ultrasonic generator of the character described to impart ultrasonic vibration to one quart of solution in a rectangular basin deep enough to permit immersing the hands, the following experiments were conducted as set forth below to determine the effectiveness of the method of this invention in comparison with the surgical scrubbing technique generally used.

One ml. of a 24-hour culture of Micrococcus pyogenes var. aureus was added to a preparation of 25 parts graphite and 5-6 parts of shortening. This black greasy pastelike preparation was rubbed onto the ventral surface of the thumb and finger-tips of the experimenters right hand.

The four finger-tips then were scrubbed manually with a A Scrubbing time, minutes: Count, organisms 0.5 1 2 40 3 27 4 v 10 5 10 Thumb (control) 180 It will be noted that even after five minutes of scrubbing,

a significant number of viable bacteria remained on the hand.

One ml. of a 24-hour culture of Microcoocus pyogenes var. aureus was added to a preparation of 25 parts graphite and 5-6 parts shortening. This black greasy pastelike preparation was rubbed onto the ventral surface of the thumb and finger-tips of the experimenters right hand. Four fingers were immersed and held substantially motionless in the container 11, which contained an aqueous solution of 15 grams of mild toilet soap, about 0.5 gram of hexachlorophene (added in the form of 15 grams per Phisohex") and water to make 1,000 ml. The ultrasonic generator was operated at 260 milliamperes. The fingers were momentarily removed from the container after exposures of 0.5, 1, 2, 3, 4 and 5 minutes; and each time they were removed, they were blotted with a sterile Immersion time, minutes gn eubsted for 48 hours at (3., count. organism l 50 2 2 3 0 4 0 5 0 Thumb (control) It will be noted that although the concentration of bactericide in this example of the method of the invention was less than in the preceding control experiment, the hands were freed from all visible evidence of foreign matter and were rendered substantially sterile in about three minutes, without any of the effort or irritation incident to scrubbing.

From these experiments it is clear that the surgical cleaning effect of the new method is markedly superior to that of the time-honored scrubbing technique. As noted above, any bactericide and any surfactant that is not injurious to the skin, in addition to those used in the foregoing experiments and otherwise particularly specified herein, may be employed with effectiveness. 'Ihus, in defining the scope of the invention in the accompanying claims, it is to be understood that the term germicide covers any of the commercially available germ-killing agents which in the dilute concentrations preferably used will not injure human skin tissue. Similarly, the term surfactant includes any of the liquid or solid soaps or non-ionic, cationic, or anionic detergents which can safely be used in contact with the skin. While in general the concentration of bactericide for most etfective results is within the broad range of 0.01% to 10% and the surfactant comprises from 1% to 10% by weight of the total aqueous solution, it is possible with some gerrnicides and surfactants to obtain satisfactory results when they are used outside these concentration limits. (Indeed, as stated above, a non-aqueous germicidal or surfactant liquid may be employed instead of a solvent in which a particular concentration of germicide or surfactant is dissolved.)

Many other departures may also be made from the preferred embodiments without departing from the scope of the invention. For example, the output frequency of the ultrasonic generator may be varied even outside the range from 10 to 200 kilocycles and still perform effectively. The power output of the ultrasonic generator may be substantially outside the abovestated range from 100 to 300 watts, depending on the shape and depth of solution in the container 11. As stated above, the portion of the body to be cleaned may be subjected to the vibrating aqueous solution for a time longer or shorter than the limit of the preferred range of ,6 to 3 minutes.

Also, while the invention is particularly well suited to cleaning a surgeons hands preparatory to operating, it can be used efiectively for other purposes, such as for cleaning the scalp in adminstering various hair and scalp treatments, for cleaning and disinfecting the feet in the treatment of various foot ailments, for cleaning a portion of the. torso or other part of the body which is to be the 4 site of a surgical operation, and for many other purposes.

I claim.

1. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing a solution of a germicide and a surfactant cleansing agent, immersing such portion of the body to be cleaned in said solution, and vibrating the solution at a frequency in the range from 10 to 200 kilocycles per second while said portion of the body is immersed therein.

2. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing a solution of a germicide and a surfactant cleansing agent, immersing such portion of the bodytobecleanedinlaidsolutioaforaperiodofl to 5 minutes, and vibrating the solution at a frequency In the range from 10 to 200 kilocycles per second while said portion of the body is immersed therein.

3. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing a solution of a germicide and a surfactant cleansing agent, immersing such portion of the body to be cleaned in said solution, and vibrating the solution at a frequency in the range from 10 to 200 kilocycles per second at a power level not exceeding five watts per sq. cm. of solution surface area while said portion of the body is immersed therein.

4. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing a solution containing 0.01% to 10% by weight of a germicide and 1% to 10% by weight of a surfactant cleansing agent, immersing such portion of the body to be cleaned in said solution, and vibrating the solution at a frequency in the range from 15 to 50 kilocycles per second while said portion of the body is immersed therein.

5. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing an aqueous solution of a germicide and a surfactant cleansing agent, immersing such portion of the body to be cleaned in said aqueous solution, and vibrating the solution at a frequencv in the range from 10 to 200 kilocycles per second while said portion of the body is immersed therein.

6. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing an aqueous solution containing 0.1% to 5% by weight of germicide and 1% to 5% by weight of a surfactant cleansing agent, immersing such portion of the body to be cleaned in said aqueous solution, and vibrating the solution at a frequency in the range from 15 to 50 kilocycles per second while said portion of the body is immersed therein.

7. A method of rendering a portion of the body selected from the scalp, torso, and limbs surgically clean which comprises preparing an aqueous solution containing 0.1% to 5% by weight of germicide and 1% to 5% by weight of a surfactant cleansing agent, immersing such portion of the body to be cleaned in said aqueous solution, for a period of be to 5 minutes, and vibrating the solution at a frequency in the range from 15 to 50 kilocycles per second and at a power level not exceeding five watts per sq. cm. of solution surface area while said portion of the body is immersed therein.

RelereneesCltedinthenleofthispatem UNITED STATES PATENTS Fessenden Oct. 14, 1919 Chambers Feb. 11, 1941 OTHERREFERENCES 

1. A METHOD OF RENDERING A PORTION OF THE BODY SELECTED FROM THE SCALP, TORSO, AND LIMBS SURGICALLY CLEAN WHICH COMPRISES PREPARING A SOLUTION OF A GERMICIDE AND A SURFACTANT CLEANSING AGENT, IMMERSING SUCH PORTION OF THE BODY TO BE CLEANED IN SAID SOLUTION, AND VIBRATING THE SOLUTION AT A FREQUENCY IN THE RANGE FROM 10 TO 200 KILOCYCLES PER SECOND WHILE SAID PORTION OF THE BODY IS IMMERSED THEREIN. 